1 package DBIx::Class::Storage::DBI::Replication;
6 use DBIx::Class::Storage::DBI;
8 use base qw/Class::Accessor::Fast/;
10 __PACKAGE__->mk_accessors( qw/read_source write_source/ );
14 DBIx::Class::Storage::DBI::Replication - Replicated database support
18 # change storage_type in your schema class
19 $schema->storage_type( '::DBI::Replication' );
20 $schema->connect_info( [
21 [ "dbi:mysql:database=test;hostname=master", "username", "password", { AutoCommit => 1 } ], # master
22 [ "dbi:mysql:database=test;hostname=slave1", "username", "password", { priority => 10 } ], # slave1
23 [ "dbi:mysql:database=test;hostname=slave2", "username", "password", { priority => 10 } ], # slave2
25 { limit_dialect => 'LimitXY' } # If needed, see below
30 This class implements replicated data store for DBI. Currently you can define one master and numerous slave database
31 connections. All write-type queries (INSERT, UPDATE, DELETE and even LAST_INSERT_ID) are routed to master database,
32 all read-type queries (SELECTs) go to the slave database.
34 For every slave database you can define a priority value, which controls data source usage pattern. It uses
35 L<DBD::Multi>, so first the lower priority data sources used (if they have the same priority, the are used
36 randomized), than if all low priority data sources fail, higher ones tried in order.
42 If you use LIMIT in your queries (effectively, if you use SQL::Abstract::Limit), do not forget to set up limit_dialect (perldoc SQL::Abstract::Limit) by passing it as an option in the (optional) hash reference to connect_info.
43 DBIC can not set it up automatically, since it can not guess DBD::Multi connection types.
49 my $class = ref( $proto ) || $proto;
52 bless( $self, $class );
54 $self->write_source( DBIx::Class::Storage::DBI->new );
55 $self->read_source( DBIx::Class::Storage::DBI->new );
63 my @sources = ($self->read_source, $self->write_source);
65 return wantarray ? @sources : \@sources;
69 my( $self, $source_info ) = @_;
71 my( $info, $global_options, $options, @dsns );
73 $info = [ @$source_info ];
75 $global_options = ref $info->[-1] eq 'HASH' ? pop( @$info ) : {};
76 if( ref( $options = $info->[0]->[-1] ) eq 'HASH' ) {
77 # Local options present in dsn, merge them with global options
78 map { $global_options->{$_} = $options->{$_} } keys %$options;
82 # We need to copy-pass $global_options, since connect_info clears it while processing options
83 $self->write_source->connect_info( [ @{$info->[0]}, { %$global_options } ] );
85 @dsns = map { ($_->[3]->{priority} || 10) => $_ } @{$info}[1..@$info-1];
86 $global_options->{dsns} = \@dsns;
88 $self->read_source->connect_info( [ 'dbi:Multi:', undef, undef, { %$global_options } ] );
92 shift->read_source->select( @_ );
95 shift->read_source->select_single( @_ );
98 shift->read_source->throw_exception( @_ );
101 shift->read_source->sql_maker( @_ );
103 sub columns_info_for {
104 shift->read_source->columns_info_for( @_ );
107 shift->read_source->sqlt_type( @_ );
110 shift->read_source->create_ddl_dir( @_ );
112 sub deployment_statements {
113 shift->read_source->deployment_statements( @_ );
115 sub datetime_parser {
116 shift->read_source->datetime_parser( @_ );
118 sub datetime_parser_type {
119 shift->read_source->datetime_parser_type( @_ );
121 sub build_datetime_parser {
122 shift->read_source->build_datetime_parser( @_ );
125 sub limit_dialect { $_->limit_dialect( @_ ) for( shift->all_sources ) }
126 sub quote_char { $_->quote_char( @_ ) for( shift->all_sources ) }
127 sub name_sep { $_->quote_char( @_ ) for( shift->all_sources ) }
128 sub disconnect { $_->disconnect( @_ ) for( shift->all_sources ) }
129 sub set_schema { $_->set_schema( @_ ) for( shift->all_sources ) }
134 undef $self->{write_source};
135 undef $self->{read_sources};
139 shift->write_source->last_insert_id( @_ );
142 shift->write_source->insert( @_ );
145 shift->write_source->update( @_ );
148 shift->write_source->update_all( @_ );
151 shift->write_source->delete( @_ );
154 shift->write_source->delete_all( @_ );
157 shift->write_source->create( @_ );
160 shift->write_source->find_or_create( @_ );
162 sub update_or_create {
163 shift->write_source->update_or_create( @_ );
166 shift->write_source->connected( @_ );
168 sub ensure_connected {
169 shift->write_source->ensure_connected( @_ );
172 shift->write_source->dbh( @_ );
175 shift->write_source->txn_begin( @_ );
178 shift->write_source->txn_commit( @_ );
181 shift->write_source->txn_rollback( @_ );
184 shift->write_source->sth( @_ );
187 shift->write_source->deploy( @_ );
191 sub debugfh { shift->_not_supported( 'debugfh' ) };
192 sub debugcb { shift->_not_supported( 'debugcb' ) };
195 my( $self, $method ) = @_;
197 die "This Storage does not support $method method.";
202 L<DBI::Class::Storage::DBI>, L<DBD::Multi>, L<DBI>
206 Norbert Csongrádi <bert@cpan.org>
208 Peter Siklósi <einon@einon.hu>
212 You may distribute this code under the same terms as Perl itself.